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4th grade

Course: 4th grade > Unit 11

Lesson 3: Parallel and perpendicular

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Parallel and perpendicular lines review

Google Classroom

Review the basics of parallel and perpendicular lines. Identify and draw parallel and perpendicular lines in some practice problems.

What are $perpendicular lines$ ‍ and $parallel lines$ ‍?

Perpendicular lines

are lines that meet at right angles.

Parallel lines

are always the same distance apart from each other — no matter how far they are extended, they will never meet.

Want to learn more about parallel and perpendicular lines? Check out this video.

Practice set 1: Identify parallel and perpendicular lines

Problem 1A

Which of the following pairs of sides in $△ G A Z$ ‍ are perpendicular?

Want to try more problems like this? Check out this exercise.

Practice set 2: Draw parallel and perpendicular lines

Problem 2A

Any pair of points can be connected by a line.

Use the green line to connect the pair of black points that makes a line parallel to the blue line segment.

Want to try more problems like this? Check out this exercise.

Want to join the conversation?

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Evan Johnson
Posted 7 years ago. Direct link to Evan Johnson's post “Quick question how do you...”
Quick question how do you prove that lines are parallel? I can't seem to find that on here and i really need to know!
Button navigates to signup pageComment on Evan Johnson's post “Quick question how do you...”
(193 votes)
Answer
- Maxwell
  Posted 7 years ago. Direct link to Maxwell's post “If you draw a line throug...”
  If you draw a line through the 2 lines, it should be perpendicular to both lines.
  Comment on Maxwell's post “If you draw a line throug...”
  (36 votes)
𝚙𝚞𝚙𝚜𝚒𝚖𝚊𝚗 🐶🥤
Posted 6 years ago. Direct link to 𝚙𝚞𝚙𝚜𝚒𝚖𝚊𝚗 🐶🥤's post “I am having trouble remem...”
I am having trouble remember these. Anyone have any tips to help me remember?

Edit : Case Closed. But thank you Taylyn for answering my question! Everyone have a nice day.
Button navigates to signup pageComment on 𝚙𝚞𝚙𝚜𝚒𝚖𝚊𝚗 🐶🥤's post “I am having trouble remem...”
(39 votes)
Answer
- Taylyn
  Posted 6 years ago. Direct link to Taylyn's post “Yes. In the word Parallel...”
  Yes. In the word Parallel, the double L's are side by side, and if going on in a straight line, would never touch. So, the double L's in Parallel are, well, parallel. Use those as an example to help you remember what parallel means.
  Comment on Taylyn's post “Yes. In the word Parallel...”
  (62 votes)
Susanparrot
Posted 7 years ago. Direct link to Susanparrot's post “Are perpendicular any ki...”
Are perpendicular any kind of lines that intersect each other? I've got to know this!
Button navigates to signup pageComment on Susanparrot's post “Are perpendicular any ki...”
(24 votes)
Answer
- Marc Joe
  Posted 6 years ago. Direct link to Marc Joe's post “Yes, perpendicular lines ...”
  Yes, perpendicular lines intersect each other with 4 90-degree angles.
  Comment on Marc Joe's post “Yes, perpendicular lines ...”
  (4 votes)
randy k
Posted 6 years ago. Direct link to randy k's post “Does a perpendicular line...”
Does a perpendicular line ALWAYS have to be 90 degrees? Just a Question
Button navigates to signup pageComment on randy k's post “Does a perpendicular line...”
(15 votes)
Answer
- Cabbage
  Posted 6 years ago. Direct link to Cabbage's post “Yes, a perpendicular line...”
  Yes, a perpendicular line must always be at a 90-degree angle
  Comment on Cabbage's post “Yes, a perpendicular line...”
  (29 votes)
Zhaojay57682
Posted 7 years ago. Direct link to Zhaojay57682's post “does perpendicular line h...”
does perpendicular line have to be the exactly 90 degrees?
Button navigates to signup pageComment on Zhaojay57682's post “does perpendicular line h...”
(9 votes)
Answer
- Arzal
  Posted 3 years ago. Direct link to Arzal's post “It always have to be exac...”
  It always have to be exactly at a right angle, and a right angle is always 90 degrees so yes.
  Button navigates to signup page
  (4 votes)
warinner
Posted 3 years ago. Direct link to warinner's post “Why does the human brain ...”
Why does the human brain have to know what geometry is?
Button navigates to signup pageComment on warinner's post “Why does the human brain ...”
(10 votes)
Answer
- Sophia Acevedo
  Posted 3 years ago. Direct link to Sophia Acevedo's post “So it can identify shapes...”
  So it can identify shapes and measure things. It also helps make the human brain grow.
  
  Hope this helps :D
  Button navigates to signup page
  (17 votes)
ger1
Posted 6 years ago. Direct link to ger1's post “What happens if a Paralle...”
What happens if a Parallel line goes through a regular line so that make it perpendicular so what is that.
Button navigates to signup pageComment on ger1's post “What happens if a Paralle...”
(13 votes)
Answer
- jessica_ghai
  Posted 5 years ago. Direct link to jessica_ghai's post “If the parallel line goes...”
  If the parallel line goes through the line, the lines will not be parallel anymore, so they will only be perpendicular if they meet at a right angle.
  Comment on jessica_ghai's post “If the parallel line goes...”
  (10 votes)
Jeffery White
Posted 5 months ago. Direct link to Jeffery White's post “to ez”
to ez
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(11 votes)
Answer
tyler_ngo502
Posted 7 months ago. Direct link to tyler_ngo502's post “Parallel Lines is two lin...”
Parallel Lines is two lines thats are the same lines together. (Cant make a picture of it but you can look it up) Notice there's two lines that are crossed? That's Perpendicular! Perpendicular Lines are two Lines that do cross
Button navigates to signup pageButton navigates to signup page
(9 votes)
Answer
Zenn
Posted 6 months ago. Direct link to Zenn's post “Gotta keep ur headup gott...”
Gotta keep ur headup gotta stay strong something aint right but u knowthat were bettertogether say what they want ill be there for u
Button navigates to signup pageComment on Zenn's post “Gotta keep ur headup gott...”
(9 votes)
Answer